Machine for rolling screwthreads on blanks

ABSTRACT

The machine for forming threads on bolts, and the like blanks by means of thread rolling tools, as described, comprises a frame, a thread rolling tool movable in the frame of the machine, said rolling tool being reciprocal along a cooperating stationary rolling tool mounted on a holding means in the frame, means for adjusting the holding means and the stationary tool; in vertical direction with respect to the direction of reciprocation of the movable tool so as to obtain the desired pitch of the screwthread on the blank; in a transverse direction perpendicular to the direction of the reciprocation so as to obtain the desired diameter of the screwthread on the blank; and in an inclined position in order to provide for the same diameter over the entire length of the threads on the blank. In this construction the holding means in the form of a block is provided with a cleft substantially in its longitudinal direction parallel to the direction of movement of the reciprocable rolling tool, said cleft ending at its bottom in a slit-shaped bore also extending in said longitudinal direction, said holding means being provided at its topside with a groove opening into said cleft, and an adjusting member in the groove for controlling the width of said groove.

finite tates atent (1 1 van de eerendonk MACE FOR ROLLWG SCREWTHREADS ONBLANKS [75] Inventor: Gerardns C. van de Meerendonk,

Helmond, Netherlands [73] Assignee: Nedschroef Octrooi MaatschappijN.V., Helmond, Netherlands [22] Filed: Apr. 7, 1971 [21] Appl. No.:132,053

[30] Foreign Application Priority Data Apr. 9, 1970 Netherlands..7005082 [52] US. Cl ..72/90 [51] Int. Cl. ..B21h 3/06 [58] Field ofSearch ..72/90, 88, 469

[56] References Cited UNITED STATES PATENTS 2,967,444 l/ 1961 Hallberget al. ..72/90 375,099 12/1887 Rogers ..72/9O 403,072 5/1889 Quimby...72/9O 1,108,425 8/1914 Brennan ...72/90 1,979,919 11/1934 Wayne...72/90 2,543,137 4/1951 Appleton..... ...72/90 2,197,732 4/1940 Olson..72/88 iii Primary Examiner-Milton S. Mehr Attorney-Pennie, Edmonds,Morton, Taylor & Adams ABSTRACT The machine for forming threads onbolts, and the like blanks by means of thread rolling tools, asdescribed, comprises a frame, a thread rolling tool movable in the frameof the machine, said rolling tool being reciprocal along a cooperatingstationary rolling tool mounted on a holding means in the frame, meansfor adjusting the holding means and the stationary tool; in verticaldirection with respect to the direction of reciprocation of the movabletool so as to obtain the desired pitch of the screwthread on the blank;in a transverse direction perpendicular to the direction of thereciprocation so as to obtain the desired diameter of the screwthread onthe blank; and in an inclined position in order to provide for the samediameter over the entire length of the threads on the blank. In thisconstruction the holding means in the form of a block is provided with acleft substantially in its longitudinal direction parallel to thedirection of movement of the reciprocable rolling tool, said cleftending at its bottom in a slit-shaped bore also extending in saidlongitudinal direction, said holding means being provided at its topsidewith a groove opening into said cleft, and an adjusting member in thegroove for controlling the width of said groove.

8 Claims, 7 Drawing Figures PATENTEU APR 1 0 I975 sum 1 OF 4 INVENTOR 4NEYS C BY x 0 V AIQH hm KOEL PAIENTEDAFEHOICYS 3 726,118

SHEET 2 0F 4 FIG. 3

. 6 Mac INVENTOR g p zwmflfih 161M TTORNEYS PATH-HEUAPRIOIQB 3,726,118

SHEET 3 OF 4 FIG. 5 v INVENTOR W,LIA-%WO3TW)MW ATTORNEYS PATENTED PR 101973 SHEET H []F 4 A TORNEYS INVENTOR M@, M lam M EMEAMM M MACHINE FGRROLLHNG SCREWTHREADS N BLANKS The present invention relates to a devicefor providing bolts and the like with screwthread by means of flatrolling tools, comprising a rolling tool movable in the frame of thedevice, said rolling tool being reciprocable along a rolling tool thatis stationary in a holding means in the frame, said holding means beingadapted to be adjusted in vertical direction with regard to thedirection of reciprocation so as to obtain the right pitch of thescrewthread, and in transverse direction perpendicularly to thedirection of reciprocation so as to obtain the right diameter of thescrewthread and in an inclined position in order to provide for the samediameter over the entire length of the screwthread.

In the device known in this field the adjustment in transverse andinclined directions has been performed up till now by means of fouradjusting bolts. The adjustment herewith is very time consuming,especially with respect to the adjustment in a more or less inclinedposition of the holding means, which is necessary, because it is a wellknown fact, that the topside of the shaft of the bolt to be treated,i.e., at its head, mostly shows the tendency to become thicker than itsbottomside. This is the consequence of the fact that when a screwthreadis rolled the material at the bottomside can somewhat flow in itslongitudinal direction.

The result is, that a greater force is exerted on the two topmostadjusting bolts than on the two lowermost bolts, so that said boltspenetrate into the material of the holder and form small pits thereinand the adjusted position is altered. Then a further adjustment of theholding means becomes necessary.

In order to obviate the disadvantages mentioned above and to simplifythe adjusting operation, in the device according to the presentinvention the holding means is provided in its longitudinal directionparallel to the direction of movement of the reciprocable rolling tool,with a cleft ending at its bottom side in a slitshaped bore alsoextending in its longitudinal direction, and is provided at its topsidewith a groove in which an adjustable member is provided for controllingthe width of said groove.

In an embodiment of the device according to the invention the groove inthe topside of the holding means has at least one hollow side wallextending conically and in said groove a wedge which is adjustable inlongitudinal direction is provided, the shape of said wedge beingadapted to the shape of said groove.

In another embodiment of the device according to the invention the meansfor carrying into effect the right diameter of the screwthread exist ofat least two adjacent adjustable wedges positioned between the holdingmeans and the frame of the device.

In the device according to the invention the preferably verticallyadjustable wedges are transversely curved at the side of the holdingmeans, said curved sides cooperating with correspondingly curved partsof the holding means.

In the drawings the device as was used up till now and an embodiment ofthe device according to the invention are illustrated by way of example.

FIG. 1 shows a side elevation of a prior art machine with a partialcross-section along the line I-I in FIG. 2 of the important portion ofthe known machine.

FIG. 2 shows a cross-section of the prior art machine along the lineiI-ll in FIG. 1.

FIG. 3 shows a plan view of the important portion of the embodimentaccording to the invention.

FIG. 4 shows a vertical cross-section along the line lV-lV in FIG. 3.

FIG. 5 shows a vertical section along the line V-V in FIG. 3.

FIG. 6 shows a side elevation of the holding means of the stationaryroller.

FIG. 7 shows a plan view of the holding means of the stationary roller.

In the known embodiment of a prior art machine as shown in FIGS. 1 and 2the transverse and inclined adjustment of the block 1, in which thestationary screwthread roller 2 is positioned, takes place by means ofthe four adjustment bolts 3, 4, 5, 6 and two drawbolts 7, 8.Last-mentioned bolts cooperate with nutshaped members 9 and 10 rotatablewithin said block, said nut-shaped members having an exterior ofcylinders. The reciprocable screwthread roller is indicated with Ill.Said roller 11 is arranged in the carriage 12. A treated bolt isindicated with 13. Furthermore the holding means 1 is fastened in itsadjusted position by the bolt 14. The adjustment of the holder 1 invertical direction takes place by means of the wedges 15 and 16.

The adjusting operation of the parts mentioned above is verytime-consuming, especially for the more or less inclined adjustment ofthe holding means. For, said inclined adjustment is necessary because itis a known fact that the top side of the shaft of the bolt to betreated, i.e., its head, mostly shows the tendency to become thickerthan its bottom side. This is the consequence of the fact that thematerial at the bottom side can flow a little lengthwise.

The result is that a greater force is exerted on the two topmostadjusting bolts than on the two lowermost bolts, so that said boltspenetrate into the material of the holding means and form small pitstherein and the adjusted position is altered again. Then a furtheradjustment of the holding means becomes necessary.

In the embodiment of the device according to the invention thereciprocable, non-adjustable screwthread roller 11 is also fastened inthe carriage 12 which is adapted to carry out a reciprocable movement ina known manner by means of a connecting rod 17.

When an object 13 to be rolled is moved to the screwthread rollers 2 and4 through the inserting finger 34 after being supplied by the supplyridges i8, 19, said rollers will carry said object along and providesame in a rotating manner with screwthread.

The stationary roller block 2 is adjustably fastened in the holdingmeans I in the frame 22 by means of clamping members 20, 21.

Said holding means 1 in the form of a block, (FIGS. 6 and 7) is providedover its entire length parallel to the direction of movement of thereciprocable screwthread roller 11 with a longitudinal cleft 23extending into or ending at the bottom side as seen in FIG. 6 in aslitshaped bore 24. Furthermore said holding means 1 is provided at itstopside with a ball-shaped groove 25 having a arcuate-shaped sides, anadjusting wedge 26 adapted to the shape of the groove 25, said wedgebeing lengthwise adjustable by means of an adjusting bolt 27 as seen inFIG. 3.

If said adjustment of the wedge 26 is carried out and said wedge e.g.,is adjusted to the lefthand side as seen in FIG. 3, it will be clearthat the portion of the holding means 1 in which the screwthread roller2 is fastened, will spread out while resiliently pivoting about animaginary pivot x (FIG. 6), said pivot thus lying underneath the rollingmember 2.

Thereby the roller member 2 will spread out more at its topside than atits bottom side so that said roller member 2 will be placed more or lessinclined.

As to the adjustment to the right screwthread diameter to be rolledthere are two conical adjusting wedges 28 and 29 which are adapted toadjust the holding means 1 forwardly and backwardly by means ofadjusting bolts 30 and 31. Said adjusting wedges 28 and 29 together forma supporting surface that is sufficiently large, so that a maladjustmentby the formation of pits is not possible.

Because of the provision of the two adjusting wedges 28 and 29 theholding means 1 needs only to be fastened by a single bolt 32. Besidesthe fact that said bolt 32 pulls the holding means 1, with the insertionof the two adjusting wedges 28 and 29, against the frame 22, saidholding means 1 is also pressed downwardly onto the frame 22 by theconical shape of said adjusting wedges 28 and 29, said two wedges and 16being positioned for that purpose underneath said screwthread roller inthe frame 22.

The adjusting operation of the device according to the present inventiontakes place as follows.

If it appears that the rolled screwthread of the article 13 has not thesame diameter everywhere, then it will be necessary to give a more orless inclination to the stationary block 1. For that purpose, after thebolt 32 has been unscrewed a little, only the adjusting bolt 27 needs tobe rotated, so that the adjusting wedge 26 is moved lengthwise and theportion of the holding means 1, in which the roller member 2 isfastened, is placed more or less inclined. Thereafter only the bolt 32needs to be refastened.

If it is necessary to readjust the screwthread diameter of the article13 to be rolled, only the two adjusting bolts 30 and 31 need to berotated after the bolt 32 has been unscrewed, so that the. wedges 28 and29 are adjusted vertically to displace the holding means 1 rearwardly orforwardly and the roller 2 is positioned nearer to or further from theroller 11.

In order to adjust the pitch, after the bolt 32 is unscrewed, theadjusting wedge 15 underneath the holding means 1 is adjusted lengthwiseby means of the bolt 33, so that the holding means 1 is adjustedvertically.

From the above it will be clear that more particularly the adjustment ofinclination of the stationary rolling member 2 has become much moresimple and can be carried out much quicker. in the known holding meansfirst three bolts must be unscrewed before the inclination can beadjusted by means of four adjusting bolts. In the novel device thisoperation is carried out after only one bolt has been unscrewed by meansof only one adjusting bolt. Also the displacement in a forward or arearward direction is much more simple. Formerly this could only takeplace by unscrewing three bolts and the adjustment by means of fourbolts. According to the present invention this operation is carried outby means of only two adjusting bolts and after that only one bolt hasbeen unscrewed.

Furthermore it is impossible that through the formation of pits in thematerial of the holding means a maladjustment can take place, becausethe two wedges 28 and 29 together form a surface that is sufficientlylarge to absorb the acting forces, so that no formation of pits ispossible.

I claim:

1. A machine for forming threads on bolts, and the like blanks by meansof thread rolling tools, comprising a frame, a thread rolling toolmovable in the frame of the machine, said rolling tool being reciprocalalong a cooperating stationary rolling tool mounted on a holding meansin the frame, means for adjusting the holding means and the stationarytool in vertical direction with respect to the direction ofreciprocation of the movable tool so as to obtain the desired pitch ofthe screwthread on the blank, in a transverse direction perpendicular tothe direction of reciprocation so as to obtain the desired diameter ofthe screwthread on the blank, and in an inclined position in order toprovide for the same diameter over the entire length of the threads onthe blank, wherein the holding means is provided with a cleft in itslongitudinal direction parallel to the direction of movement of thereciprocable rolling tool, said cleft ending at its bottom in aslit-shaped bore also extending in said longitudinal direction, saidholding means being provided at its topside with a groove opening intosaid cleft, and an adjusting member in the groove for controlling thewidth of said groove.

2. A machine as claimed in claim 1, wherein the holding means comprisesa block mounted on the frame of the machine in which said cleft, saidslitshaped bore and said groove are provided.

3. A machine as claimed in claim 1, wherein one side wall of said grooveis concave, and in which said adjusting member comprises a wedge fittingin said groove.

4. A machine as claimed in claim 1, wherein the adjusting means forobtaining the desired diameter of the screwthread on the blank comprisesspaced wedges located between the holding means andthe frame of themachine.

5. A machine as claimed in claim 4, wherein said spaced wedges arearcuate in a transverse direction,

and cooperating with arcuate recesses in the side of the holding meansopposite the stationary rolling tool mounted thereon.

6. A machine as claimed in claim 5, including a bolt securing andbiasing the holding means toward the frame of the machine, said boltextending at right angles to the operative plane of the stationarythreading tool and serving to clamp said spaced wedges in their adjustedpositions.

7. In a machine for forming threads on bolts, and the like blanks bymeans of thread rolling tools, including a frame, a movable threadrolling tool cooperating with a stationary thread rolling tool mountedon a holding block mounted in the frame, said movable rolling tool beingreciprocal along the stationary rolling tool,

means for adjusting the holding block and the stationary tool includingmeans for adjusting the inclination of the stationary tool in order toprovide for the same diameter over the entire length of the threads onthe blank, comprising a holding block having a cleft therein in itslongitudinal direction parallel to the direction of movement of thereciprocable thread rolling tool, said 6 cleft extending from the upperportion of the block into ry tool. its lower portion, said holding blockbeing provided at 8. A machine as claimed in claim 7, wherein the botitsto ide ith a roo t di along d opening tom of the cleft is located in thelower portion of the into said cleft, and an adjusting member in saidgroove mock below the P of the summary toolfor varying its width and theinclination of the stationa- 5

1. A machine for forming threads on bolts, and the like blanks by meansof thread rolling tools, comprising a frame, a thread rolling toolmovable in the frame of the machine, said rolling tool being reciprocalalong a cooperating stationary rolling tool mounted on a holding meansin the frame, means for adjusting the holding means and the stationarytool in vertical direction with respect to the direction ofreciprocation of the movable tool so as to obtain the desired pitch ofthe screwthread on the blank, in a transverse direction perpendicular tothe direction of reciprocation so as to obtain the desired diameter ofthe screwthread on the blank, and in an inclined position in order toprovide for the same diameter over the entire length of the threads onthe blank, wherein the holding means is provided with a cleft in itslongitudinal direction parallel to the direction of movement of thereciprocable rolling tool, said cleft ending at its bottom in aslit-shaped bore also extending in said longitudinal direction, saidholding means being provided at its topside with a groove opening intosaid cleft, and an adjusting member in the groove for controlling thewidth of said groove.
 2. A machine as claimed in claim 1, wherein theholding means comprises a block mounted on the frame of the machine inwhich said cleft, said slit-shaped bore and said groove are provided. 3.A machine as claimed in claim 1, wherein one side wall of said groove isconcave, and in which said adjusting member comprises a wedge fitting insaid groove.
 4. A machine as claimed in claim 1, wherein the adjustingmeans for obtaining the desired diameter of the screwthread on the blankcomprises spaced wedges located between the holding means and the frameof the machine.
 5. A machine as claimed in claim 4, wherein said spacedwedges are arcuate in a transverse direction, and cooperating witharcuate recesses in the side of the holding means opposite thestationary rolling tool mounted thereon.
 6. A machine as claimed inclaim 5, including a bolt securing and biasing the holding means towardthe frame of the machine, said bolt extending at right angles to theoperative plane of the stationary threading tool and serving to clampsaid spaced wedges in their adjusted positions.
 7. In a machine forforming threads on bolts, and the like blanks by means of thread rollingtools, including a frame, a movable thread rolling tool cooperating witha stationary thread rolling tool mounted on a holding block mounted inthe frame, said movable rolling tool being reciprocal along thestationary rolling tool, means for adjusting the holding block and thestationary tool including means for adjusting the inclination of thestationary tool in order to provide for the same diameter over theentire length of the threads on the blank, comprising a holding blockhaving a cleft therein in its longitudinal direction parallel to thedirection of movement of the reciprocable thread rolling tool, saidcleft extending from the upper portion of the block into its lowerportion, said holding block being provided at its topside with a grooveextending along and opening into said cleft, and an adjusting member insaid groove for varying its width and the inclination of the stationarytool.
 8. A machine as claimed in claim 7, wherein the bottom of thecleft is located in the lower portion of the block below the position ofthe stationary tool.